In recent years, in a living space near one's own residential area and including the residential area, a demand to measure environmental radiation doses has been increasing. In response to such a demand, portable dosimeters for measuring environmental radiation doses are starting to spread.
For example, an environmental radiation monitoring apparatus described in Patent Literature 1 includes: many mobile slave stations that measure radiation doses at measuring sites; and a master station that performs data processing in a location distant from the slave stations, and is configured such that each of the slave stations is provided with: a GPS receiver that senses its installation location; a radiation measuring device that measures a radiation dose at regular time intervals, and a data transmission device that wirelessly transmits sensed location data and measured radiation dose data to the master station, and the master station is provided with: a data reception device that receives location data and radiation dose data transmitted from each of the slave stations; and a data processor that performs data processing for instantaneously storing pieces of received dada in a database to draw a contour map of a radiation dose rate in real time, and superimposing the contour map on a geographical information system to create an image as a radiation dose rate map of a measurement area.
However, in the conventional radiation monitoring apparatus, a user interface used at the time of plotting pieces of radiation measurement data on a map is not considered at all.
Also, many problems related to a user interface still remain unsolved, such that it becomes extremely hard to read the map due to complexity of the map and operability becomes worse at the time of selecting measurement data to display the data on the map when displaying all peaces of measurement data.
Further, such problems occur not only in a radiation measuring device but also in measuring devices used in the case where a relationship between a measurement location and measurement data has a significant meaning, such as measuring devices for environmental states such as CO2 concentration, NOx concentration, and a pH level, and mobile type vehicle measuring device such as a tachograph. That is, in the case of frequently moving to make measurements at respective locations, or installing measuring devices at many spots, reflecting pieces of measurement data on a map with the simplest possible operation is considered to be an important challenge for many people to know a value distribution or the like of the pieces of measurement data.